nificance, although they had intimate relations with the Zaidites of Southern Arabia. As first Egypt and afterwards Turkey made their protectorate over the holy cities more effective, the princes of Mecca became orthodox.
The Zaidites, who settled in Yemen from the ninth century on, are really Shîʿites, although of the most moderate kind. Without striving after expansion outside Arabia, they firmly refuse to give up their own Khalifate and to acknowledge the sovereignty of any non-Alid ruler; the efforts of the Turks to subdue them or to make a compromise with them have had no lasting results. This is the principal obstacle against their being included in the orthodox community, although their admission is defended, even under present circumstances, by many non-political Moslim scholars. The Zaidites are the remnant of the original Arabian Shîʿah, which for centuries has counted adherents in all parts of the Moslim world, and some of whose tenets have penetrated Mohammedan orthodoxy. The almost general veneration of the sayyids and sherîfs, as the descendants of Mohammed are entitled, is due to this influence.
The Shîʿah outside Arabia, whose adherents used to be persecuted by the official authorities, not without good cause, became the receptacle of all the revolutionary and heterodox ideas maintained by the converted peoples. Alongside of the visible political history of Islâm of the first cen-
